1 files changed, 404 insertions, 0 deletions
diff --git a/drivers/nfc/mei_phy.c b/drivers/nfc/mei_phy.c
new file mode 100644
index 000000000..0f43bb389
--- /dev/null
+++ b/drivers/nfc/mei_phy.c
@@ -0,0 +1,404 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2013, Intel Corporation.
+ *
+ * MEI Library for mei bus nfc device access
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/nfc.h>
+
+#include "mei_phy.h"
+
+struct mei_nfc_hdr {
+	u8 cmd;
+	u8 status;
+	u16 req_id;
+	u32 reserved;
+	u16 data_size;
+} __packed;
+
+struct mei_nfc_cmd {
+	struct mei_nfc_hdr hdr;
+	u8 sub_command;
+	u8 data[];
+} __packed;
+
+struct mei_nfc_reply {
+	struct mei_nfc_hdr hdr;
+	u8 sub_command;
+	u8 reply_status;
+	u8 data[];
+} __packed;
+
+struct mei_nfc_if_version {
+	u8 radio_version_sw[3];
+	u8 reserved[3];
+	u8 radio_version_hw[3];
+	u8 i2c_addr;
+	u8 fw_ivn;
+	u8 vendor_id;
+	u8 radio_type;
+} __packed;
+
+struct mei_nfc_connect {
+	u8 fw_ivn;
+	u8 vendor_id;
+} __packed;
+
+struct mei_nfc_connect_resp {
+	u8 fw_ivn;
+	u8 vendor_id;
+	u16 me_major;
+	u16 me_minor;
+	u16 me_hotfix;
+	u16 me_build;
+} __packed;
+
+
+#define MEI_NFC_CMD_MAINTENANCE 0x00
+#define MEI_NFC_CMD_HCI_SEND 0x01
+#define MEI_NFC_CMD_HCI_RECV 0x02
+
+#define MEI_NFC_SUBCMD_CONNECT    0x00
+#define MEI_NFC_SUBCMD_IF_VERSION 0x01
+
+#define MEI_NFC_MAX_READ (MEI_NFC_HEADER_SIZE + MEI_NFC_MAX_HCI_PAYLOAD)
+
+#define MEI_DUMP_SKB_IN(info, skb)				\
+do {								\
+	pr_debug("%s:\n", info);				\
+	print_hex_dump_debug("mei in : ", DUMP_PREFIX_OFFSET,	\
+			16, 1, (skb)->data, (skb)->len, false);	\
+} while (0)
+
+#define MEI_DUMP_SKB_OUT(info, skb)				\
+do {								\
+	pr_debug("%s:\n", info);				\
+	print_hex_dump_debug("mei out: ", DUMP_PREFIX_OFFSET,	\
+			16, 1, (skb)->data, (skb)->len, false);	\
+} while (0)
+
+#define MEI_DUMP_NFC_HDR(info, _hdr)                                \
+do {                                                                \
+	pr_debug("%s:\n", info);                                    \
+	pr_debug("cmd=%02d status=%d req_id=%d rsvd=%d size=%d\n",  \
+		 (_hdr)->cmd, (_hdr)->status, (_hdr)->req_id,       \
+		 (_hdr)->reserved, (_hdr)->data_size);              \
+} while (0)
+
+static int mei_nfc_if_version(struct nfc_mei_phy *phy)
+{
+
+	struct mei_nfc_cmd cmd;
+	struct mei_nfc_reply *reply = NULL;
+	struct mei_nfc_if_version *version;
+	size_t if_version_length;
+	int bytes_recv, r;
+
+	pr_info("%s\n", __func__);
+
+	memset(&cmd, 0, sizeof(struct mei_nfc_cmd));
+	cmd.hdr.cmd = MEI_NFC_CMD_MAINTENANCE;
+	cmd.hdr.data_size = 1;
+	cmd.sub_command = MEI_NFC_SUBCMD_IF_VERSION;
+
+	MEI_DUMP_NFC_HDR("version", &cmd.hdr);
+	r = mei_cldev_send(phy->cldev, (u8 *)&cmd, sizeof(struct mei_nfc_cmd));
+	if (r < 0) {
+		pr_err("Could not send IF version cmd\n");
+		return r;
+	}
+
+	/* to be sure on the stack we alloc memory */
+	if_version_length = sizeof(struct mei_nfc_reply) +
+		sizeof(struct mei_nfc_if_version);
+
+	reply = kzalloc(if_version_length, GFP_KERNEL);
+	if (!reply)
+		return -ENOMEM;
+
+	bytes_recv = mei_cldev_recv(phy->cldev, (u8 *)reply, if_version_length);
+	if (bytes_recv < 0 || bytes_recv < if_version_length) {
+		pr_err("Could not read IF version\n");
+		r = -EIO;
+		goto err;
+	}
+
+	version = (struct mei_nfc_if_version *)reply->data;
+
+	phy->fw_ivn = version->fw_ivn;
+	phy->vendor_id = version->vendor_id;
+	phy->radio_type = version->radio_type;
+
+err:
+	kfree(reply);
+	return r;
+}
+
+static int mei_nfc_connect(struct nfc_mei_phy *phy)
+{
+	struct mei_nfc_cmd *cmd, *reply;
+	struct mei_nfc_connect *connect;
+	struct mei_nfc_connect_resp *connect_resp;
+	size_t connect_length, connect_resp_length;
+	int bytes_recv, r;
+
+	pr_info("%s\n", __func__);
+
+	connect_length = sizeof(struct mei_nfc_cmd) +
+			sizeof(struct mei_nfc_connect);
+
+	connect_resp_length = sizeof(struct mei_nfc_cmd) +
+			sizeof(struct mei_nfc_connect_resp);
+
+	cmd = kzalloc(connect_length, GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+	connect = (struct mei_nfc_connect *)cmd->data;
+
+	reply = kzalloc(connect_resp_length, GFP_KERNEL);
+	if (!reply) {
+		kfree(cmd);
+		return -ENOMEM;
+	}
+
+	connect_resp = (struct mei_nfc_connect_resp *)reply->data;
+
+	cmd->hdr.cmd = MEI_NFC_CMD_MAINTENANCE;
+	cmd->hdr.data_size = 3;
+	cmd->sub_command = MEI_NFC_SUBCMD_CONNECT;
+	connect->fw_ivn = phy->fw_ivn;
+	connect->vendor_id = phy->vendor_id;
+
+	MEI_DUMP_NFC_HDR("connect request", &cmd->hdr);
+	r = mei_cldev_send(phy->cldev, (u8 *)cmd, connect_length);
+	if (r < 0) {
+		pr_err("Could not send connect cmd %d\n", r);
+		goto err;
+	}
+
+	bytes_recv = mei_cldev_recv(phy->cldev, (u8 *)reply,
+				    connect_resp_length);
+	if (bytes_recv < 0) {
+		r = bytes_recv;
+		pr_err("Could not read connect response %d\n", r);
+		goto err;
+	}
+
+	MEI_DUMP_NFC_HDR("connect reply", &reply->hdr);
+
+	pr_info("IVN 0x%x Vendor ID 0x%x\n",
+		 connect_resp->fw_ivn, connect_resp->vendor_id);
+
+	pr_info("ME FW %d.%d.%d.%d\n",
+		connect_resp->me_major, connect_resp->me_minor,
+		connect_resp->me_hotfix, connect_resp->me_build);
+
+	r = 0;
+
+err:
+	kfree(reply);
+	kfree(cmd);
+
+	return r;
+}
+
+static int mei_nfc_send(struct nfc_mei_phy *phy, u8 *buf, size_t length)
+{
+	struct mei_nfc_hdr *hdr;
+	u8 *mei_buf;
+	int err;
+
+	err = -ENOMEM;
+	mei_buf = kzalloc(length + MEI_NFC_HEADER_SIZE, GFP_KERNEL);
+	if (!mei_buf)
+		goto out;
+
+	hdr = (struct mei_nfc_hdr *)mei_buf;
+	hdr->cmd = MEI_NFC_CMD_HCI_SEND;
+	hdr->status = 0;
+	hdr->req_id = phy->req_id;
+	hdr->reserved = 0;
+	hdr->data_size = length;
+
+	MEI_DUMP_NFC_HDR("send", hdr);
+
+	memcpy(mei_buf + MEI_NFC_HEADER_SIZE, buf, length);
+	err = mei_cldev_send(phy->cldev, mei_buf, length + MEI_NFC_HEADER_SIZE);
+	if (err < 0)
+		goto out;
+
+	if (!wait_event_interruptible_timeout(phy->send_wq,
+				phy->recv_req_id == phy->req_id, HZ)) {
+		pr_err("NFC MEI command timeout\n");
+		err = -ETIME;
+	} else {
+		phy->req_id++;
+	}
+out:
+	kfree(mei_buf);
+	return err;
+}
+
+/*
+ * Writing a frame must not return the number of written bytes.
+ * It must return either zero for success, or <0 for error.
+ * In addition, it must not alter the skb
+ */
+static int nfc_mei_phy_write(void *phy_id, struct sk_buff *skb)
+{
+	struct nfc_mei_phy *phy = phy_id;
+	int r;
+
+	MEI_DUMP_SKB_OUT("mei frame sent", skb);
+
+	r = mei_nfc_send(phy, skb->data, skb->len);
+	if (r > 0)
+		r = 0;
+
+	return r;
+}
+
+static int mei_nfc_recv(struct nfc_mei_phy *phy, u8 *buf, size_t length)
+{
+	struct mei_nfc_hdr *hdr;
+	int received_length;
+
+	received_length = mei_cldev_recv(phy->cldev, buf, length);
+	if (received_length < 0)
+		return received_length;
+
+	hdr = (struct mei_nfc_hdr *) buf;
+
+	MEI_DUMP_NFC_HDR("receive", hdr);
+	if (hdr->cmd == MEI_NFC_CMD_HCI_SEND) {
+		phy->recv_req_id = hdr->req_id;
+		wake_up(&phy->send_wq);
+
+		return 0;
+	}
+
+	return received_length;
+}
+
+
+static void nfc_mei_rx_cb(struct mei_cl_device *cldev)
+{
+	struct nfc_mei_phy *phy = mei_cldev_get_drvdata(cldev);
+	struct sk_buff *skb;
+	int reply_size;
+
+	if (!phy)
+		return;
+
+	if (phy->hard_fault != 0)
+		return;
+
+	skb = alloc_skb(MEI_NFC_MAX_READ, GFP_KERNEL);
+	if (!skb)
+		return;
+
+	reply_size = mei_nfc_recv(phy, skb->data, MEI_NFC_MAX_READ);
+	if (reply_size < MEI_NFC_HEADER_SIZE) {
+		kfree_skb(skb);
+		return;
+	}
+
+	skb_put(skb, reply_size);
+	skb_pull(skb, MEI_NFC_HEADER_SIZE);
+
+	MEI_DUMP_SKB_IN("mei frame read", skb);
+
+	nfc_hci_recv_frame(phy->hdev, skb);
+}
+
+static int nfc_mei_phy_enable(void *phy_id)
+{
+	int r;
+	struct nfc_mei_phy *phy = phy_id;
+
+	pr_info("%s\n", __func__);
+
+	if (phy->powered == 1)
+		return 0;
+
+	r = mei_cldev_enable(phy->cldev);
+	if (r < 0) {
+		pr_err("Could not enable device %d\n", r);
+		return r;
+	}
+
+	r = mei_nfc_if_version(phy);
+	if (r < 0) {
+		pr_err("Could not enable device %d\n", r);
+		goto err;
+	}
+
+	r = mei_nfc_connect(phy);
+	if (r < 0) {
+		pr_err("Could not connect to device %d\n", r);
+		goto err;
+	}
+
+	r = mei_cldev_register_rx_cb(phy->cldev, nfc_mei_rx_cb);
+	if (r) {
+		pr_err("Event cb registration failed %d\n", r);
+		goto err;
+	}
+
+	phy->powered = 1;
+
+	return 0;
+
+err:
+	phy->powered = 0;
+	mei_cldev_disable(phy->cldev);
+	return r;
+}
+
+static void nfc_mei_phy_disable(void *phy_id)
+{
+	struct nfc_mei_phy *phy = phy_id;
+
+	pr_info("%s\n", __func__);
+
+	mei_cldev_disable(phy->cldev);
+
+	phy->powered = 0;
+}
+
+struct nfc_phy_ops mei_phy_ops = {
+	.write = nfc_mei_phy_write,
+	.enable = nfc_mei_phy_enable,
+	.disable = nfc_mei_phy_disable,
+};
+EXPORT_SYMBOL_GPL(mei_phy_ops);
+
+struct nfc_mei_phy *nfc_mei_phy_alloc(struct mei_cl_device *cldev)
+{
+	struct nfc_mei_phy *phy;
+
+	phy = kzalloc(sizeof(struct nfc_mei_phy), GFP_KERNEL);
+	if (!phy)
+		return NULL;
+
+	phy->cldev = cldev;
+	init_waitqueue_head(&phy->send_wq);
+	mei_cldev_set_drvdata(cldev, phy);
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(nfc_mei_phy_alloc);
+
+void nfc_mei_phy_free(struct nfc_mei_phy *phy)
+{
+	mei_cldev_disable(phy->cldev);
+	kfree(phy);
+}
+EXPORT_SYMBOL_GPL(nfc_mei_phy_free);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("mei bus NFC device interface");